Installing an AC Grounding System, Need Advice


Later this week, my electician will begin work on my electric project, which will involve the installation of a 7.5kVA isolation transformer that will be fed from a separate meter tap. The isolation transformer will be installed in front of a new dedicated circuit panel that will house the dedicated circuits that will feed my listening room. All the dedicated circuits will be fed from the same side of the bar in the new panel in order to maintain consistent phase.

As Sean has advised in a separate thread, I know it is important that I check - and upgrade as necessary - the ground for my AC system. (My house was built in the late 1950s, and, from the looks of things, not much has been done since that time to upgrade the electric service. So I am nearly certain that I will find the grounding system leaves much to be desired.) I also know from discussion in various other threads that it is important for the entire electrical system in my house to share a common ground. So I expect that I will need to upgrade the grounding system into my main circuit panel and then tie the isolation transformer and the new dedicated panel back to that same grounding system.

The work on my house is being performed by a qualified electrician, but, as I have noted in other threads, I would like advice on the audiophile details that can make a difference in the sound (in this case, the noise floor) of my system. Perhaps I should also mention that my plan involves installing a separate dedicated circuit for each of my seven components. Given that this sort of a set-up is more prone to ground loops, I am interested in advice regarding how to avoid them with this set-up.

With that as background, would any of the resident experts be willing to share with me the details of how to install a high quality grounding system for my AC power? I would appreciate as much detail as possible regarding the materials to use as well as installation advice.

I have read some advice in other threads recommending two separate copper grounding rods driven into the ground relatively close to each other with a weather-proofed connection between the two rods that is, in turn connected to the electrical system. I have also seen some advice that I believe involves wiring one of these connected ground rods to the main house circuit panel and the other connected ground rod to the audio portion of the system (i.e., in my case, the isolation transformer and the new dedicated circuit panel). Please let me know if this is headed in the right direction and, if so, please help me to fill in some details (dimensions of the copper, advice on how to drive it into the ground without mangling it, distance between the redundant rods, any other details you see fit).

As always, thanks for your help and patience.
cincy_bob

Showing 2 responses by talon4

Jea48, the "water method" that you commented about is the method that was used by my electrician to drive the rod. The power was disconnected and the ground wire hadn't been connected to the rod yet. My electrician works for the one of the biggest electrical contractors in town. Are you saying that what he did wasn't legal? I've heard others use this method in my area as well.
I'd check out www.equitech.com. They're the people into balanced power; however, they also have different articles that can be downloaded via computer. One of these articles is "setting up an a/c ground." I used one 10' 5/8" copper ground rod. If you use two, they need to be separated by at least 8'. As for putting the ground rod into the ground... Use water. Slowly dribble it into the hole that the rod is making, as you plunge it up and down. The pressure of the rod tip--(like a high heel shoe-pressure per square inch, ouch!), and the water at the hole's developing surface will cut through the dirt in no time. Be careful with that project. I've read multiple grounds can be dangerous. Hope all this helps. Good Listening!